Locking OpenLP to KDE-Plasma Task Manager

[Ashley]

Kubuntu 12.04
KDE 4.8.4
OpenLP 1.9.10

Run OpenLP.
Then right-click on the icon in the bottom panel Task Manager plasmoid and select "Show A Launcher When Not Running".
A window pops up says "The application, to which this task is associated with, could not be determined. Please select the appropriate application from the list below."
When you do this it looks like all is working as excpected but when you close OpenLP and reopen it, a new OpenLP icon appears.

After digging a bit and trying it in Unity (which has a similar problem except after reopening it just shows the locked icon and no indicators to show its running and clicking on the icon trys to start a new instance of OpenLP), I found that if I ran "xprop" and click on the OpenLP window, it shows WM_CLASS(STRING) = "", ""

On other programs, that don't have this issue, the WM_CLASS strings are not empty.
e.g. WM_CLASS(STRING) = "dolphin", "Dolphin" or WM_CLASS(STRING) = "Mail", "Thunderbird"

[Raoul Snyman (raoul-snyman)]

Note to self: http://doc.qt.nokia.com/4.7/qx11info.html#appClass